I was looking at this picture and it says water temperature sensor (for ip Guage) and Im confused it thats the one for the in cab guage. My temp guage is always on 275 weather the engine is hot or cold but still returns to 0 when key is off so Im guessing its the sender.

 

yes its the sender...

 

Look here (right at the back and up top):

 

The water temp gauge in my dash stopped working the other day, so I ordered a new sensor and went to put it in today. I can't find it. I've looked at the diagram above, but where it says the sensor is, all there is is a plug. No wires, no sensor, no nothing. Where the hell is this thing?